This invention pertains to the art of fluid conduits and, more particularly, to an improved protective cap for the end face of such a conduit.
The invention is particularly applicable to a protective cap adapted to shield the sealing beads of a gland member used in a tube coupling assembly before the gland member is coupled to a second gland member and will be described with reference thereto. However, it will be appreciated by those skilled in the art that the invention has far broader applications and may be adapted for use in a wide variety of environments where a protective cap is employed and where it is desired to shield or protect an end or sealing face of a fluid conduit prior to its use in a fluid line system.
One particular known type of gland member utilized in tube coupling assemblies has an end face provided with a ring-like sealing bead. The bead has a highly polished sealing surface and any nicks or scratches on it impede proper sealing. This is particularly important if the gland is used in the handling of harmful gases such as, for example, cyanide, which is widely used in the semi-conductor industry. In general, tube coupling members which are designed for use at both high and low temperatures and at both high pressures and vacuums must have smooth and polished sealing surfaces in order to preserve the capacity to seal under such varying temperature and pressure conditions. It is thus necessary to protect the sealing surfaces of a tube coupling member prior to its installation in a tubing system.
Although several types of end protector caps are known for pipe ends, none of these had the particular characteristics necessary for protecting the sealing surfaces of a fluid conduit member in an adequate manner. With regard to known metal protective caps, none of these is so configured that an end face of the cap is spaced from the sealing face of the associated fluid conduit to prevent the scratching or marring of the sealing face. Moreover, none of the known protective caps is so configured as to allow the purging of gases from the associated fluid conduit member when it is being welded to another fluid conduit member. Also, unless the protective cap is made of a metal compatible with the metal from which the fluid conduit is made, galvanic corrosion between the two might occur in corrosive environments.
Another known type of protector cap is made of plastic which has the disadvantage that it releases particulates and/or hydrocarbons onto the sealing face of the fluid conduit member. Moreover, plastic caps cannot withstand the same temperatures and chemicals as the metal conduit members they are meant to protect and thus afford inadequate protection in hostile environments.
The present invention contemplates a new and improved protective cap member which is simple in design, effective in use, and overcomes the foregoing difficulties and others while providing better and more advantageous overall results.